Spark-plug



E. J. GAGNIER.

SPARK PLUG. I APPLICATION man AUG-14, 9m

Patented Feb. 15, 1921.

WWW,

PATENT OFFICE.

ELMER J. GAGNIER, OF DETROIT, MICHIGAN.

SPARK-PLUG.

Specification of Letters Patent.

Patented Feb. 15, 1921.

Application filed August 14, 1919. Serial No. 317,429.

To all whom it may concern:

Be it known that I ELMER J. GAGNIER, citizen of the United tates, residing at Detroit, county of Wayne, State of Michigan, have invented a certain new and useful Improvement in Spark-Plugs,,and declare the following to be a full, clear, and exact description of the same, such as .7 will enable others skilled in the art to which it pertains to make and use the. same, reference being had to the accompanying drawings, which form a part of this specification.

My invention relates to an improvement in spark plugs, the object being to provide a spark plug simple of construction and inexpensive to build, which is so constructed that the actual operation of the plug will prevent carbon formations on the porcelain insulating core and short circuiting will be reduced to'the lowest possible minimum.

In the drawings Figure 1 is an elevation of my improved spark plug, partly in section.

' Fig. 2 is a plan view of the concave closure disk 01 found in Fig. 1.

Fig. 3 is a sectional view of a modification showing'a flat closure disk crimped into place.

Fig. 4 is a plan view disk. 7

Insulating core a, through which is passed the central electrode 6 forming a gas-tight of the flat closure contact therethrough by being cemented therein or in other approved manner, is partially inclosed, and is carried. by a metal casing composed of male and female members b and a. Member I) is externally screwthreaded so as to be inserted in the cylinder.

The central electrode e is externallythreaded at its upper extremity to receive the Jam nut g which holds the wire terminal 11 in place. A bell washer j is provided which serves as a protective hood for the exposed end of the porcelain core, and is held in place by means of a nut k.

Conventional gaskets are provided as indicated by letters 70-70. These are of the usual type as adapted for use in a plug in a conventional way.

In Fig. 1 the closure disk d, made of a material which will serve as a good conductor, is crimped into place at the lower end of metallic member I). This disk is provided with a central opening d through which the teat of the porcelain core proshort circuit.

jects and against which it abuts. The exposure of teat of the insulating core below the disk d is sufiicient to provide the desired gap across which the spark will jump from the central electrode to the inner periphery of the closure disk.

It will be obvious that oil, dirt or fouling of any sort will be kept from the interior of the plug and from the porcelain core, with the exception of the exposed teat portion, and carbonization and short circuiting will be reduced to the lowest possible mimmum.

Thus far the operation of the plug would be identical whether the-form shown in Fig. 1, or the form shownin Fig. 3 were used. In Fig. 3', a flat disk f provided with central o ening f is provided and is crimped into p ace in manner similar to that shown in Flg. 1. It would be a somewhat easier method of construction. In either instance the passage of the spark from the central electrode to the disk would burn 01f any carbon or dirt tending to collect on the exposed of the insulation extending below said Through the use of a dished disk, as shown in Fig. 1, any oil which might splash on the disk would drip down either oil the outer edge thereof or along the edge of the porcelain and would not collect thereon and foul the same.

A further object of the bell shaped washer is to prevent moisture collecting on' the exposed end of the insulating core causing a The moisture collecting on the bell shaped washer however, would drip oif clearing the porcelain insulation.

Having thus described my invention, what I claim is:

1. In a spark plug, a conductive disk provided with a central opening held in position as a closure at the lower end of the casing of said plug, an insulating core pro-v vided with a central electrode, the lower end 100 of said core being fashioned as a teat to project through the opening in said closure disk and beyond the same.

2. In a spark plug, a conductive disk provided with an opening therethrough, held in 105 position as a closure at the sparking end of said plug, an insulating core provided with a central electrode, the lower cone-shaped end of said core projected through the open ing in said disk, abutting the same in such 110 washer a manner that the electrode carried thereby Will be disposed within sparking proximity to said disk.

3. In aspark plug, a conductive disk provided with a central opening held in position as a closure at the lower end of the easing of said plug, an insulating core provided with a central electrode integral therewith, the lower end of said core fashioned as a teat to project through said opening abutting closely said disk to form a tight joint therewith, and projecting slightly beyond said disk, the end of said central electrode projecting beyond said insulating core and disposed in sparking proximity to said disk.

4. In a spark plug, an insulating core carrying a central electrode passing centrally longitudinallytherethrough, a metal casing formed of male and female members partially inclosing said core, a bell-shaped adapted, to fit over the upper exposed end of said insulating core and be held in place by a nut screwed'into position on the upper extremity of said central electrode, a conductive disk provided with a central opening positioned as a closure at the cylinder end 01? said metal casing, the lower end of said insulating core adapted to pass through said central opening closely abutting said disk and projecting exteriorly thereof, disposing said projecting central electrode in sparking proximity to said conductive disk.

5. In a spark plug, a conductive concave disk provided with .a central opening held in position as a closure. at the lower end of the casing of said plug, an insulating core provided with a central electrode, the lower end'of which core is fashioned in form of a teat to project through the opening in said closure disk and beyond the same.

In testimony whereof, I sign this specification.

' ELMER J. GAGNIER. 

